Learning from Follensby

Science preserve at Follensby Pond aims to understand, protect unique freshwater ecosystem

By Zachary Matson

Dirk Bryant, director of lands for The Nature Conservancy’s Adirondack chapter, said the McCormick family that long owned Follensby Pond and the surrounding land had a simple rule for anglers lucky enough to throw a line into the remote Adirondack lake.

“One fish and that was it,” Bryant said.

That legacy of conservation-minded ownership and minimal access helped sustain one of the finest examples of an old-age population of native lake trout— not just in the Adirondacks but the entire country. 

Now 15 years after TNC purchased the property from the McCormicks, the conservation nonprofit plans to maintain the 970-acre lake and its watershed as a 8,600-acre special freshwater research preserve, potentially one of the first of its kind in the world.

The science carried out at Follensby will be guided by a consortium of research institutions, environmental groups and state representatives after TNC and the state finalize a pair of conservation easements that will govern the research and education effort, as well as public access to a 6,000-acre parcel along the western shore of the Raquette River. 

The consortium includes TNC, the state Department of Environmental Conservation, Cornell University, the Adirondack Watershed Institute at Paul Smith’s College, SUNY College of Environmental Science and Forestry, U.S. Fish and Wildlife Service and U.S. Geological Survey. 

TNC and state leaders are also promising the lake will be accessible for educational purposes, which could open opportunities for everything from local elementary school field trips to doctoral research projects. The Wild Center is partnering to facilitate interpretative experiences for lifelong learners as well.   

“We are going through the process of how do we balance all of the potential we have for science and freshwater protection with opening it for public access,” said Peg Olsen, director of the conservancy’s Adirondack chapter. “We know there are a lot of folks interested in enjoying the Raquette River shoreline as well as Follensby.”

What’s there

After acquiring the 14,600-acre property in 2008 and while working through other land deals with the state, TNC funded research to evaluate the Follensby Pond fishery and what should become of it.  

In a study published in 2016, the lake’s only scientific survey to date, researchers estimated Follensby’s population of lake trout at least a year old at around 7,300, including around 2,300 considered a fishable size, 1,300 at sexual maturity and a little more than 100 trophy-sized trout topping 30 inches. The lake’s trout were estimated to reach up to 24 years old.

Chris Solomon, an aquatic ecologist at the Cary Institute for Ecosystem Studies who helped lead the Follensby research, in a recent interview cautioned that it is challenging to estimate an accurate population count.  

The study focused on simulating how the trout population would respond to different regimes of fishing regulations — from catch and release to various size and haul restrictions.

The results suggested that Follensby’s slow-growing and slow-maturing lake trout population could be threatened if opened to anglers. Even if the population seems large, Solomon said, with such slow sexual maturation, fishing could quickly threaten the population. 

“The take-home summary of our work is that it’s a population that is extremely vulnerable to overexploitation.”

Chris Solomon, an aquatic ecologist at the Cary Institute for Ecosystem Studies

While conducting field work, the researchers also documented a novel behavior from some of the lake’s cisco, another cold-water species. They spotted pregnant cisco gathering at the small dam at the lake’s outlet, returning to the lake after apparently migrating out through the Raquette River stream network.

Typically, cisco living in inland lakes move closer to shore to spawn, while only cisco in Hudson Bay or large systems like the Great Lakes migrate up tributaries. In Follensby’s case, cisco may spend time in other lakes along the Raquette, such as Tupper Lake or Stony Creek Ponds, or in the river itself, before returning to Follensby, Solomon and his colleagues theorized.   

The underlying migratory behavior remains a mystery but if confirmed could represent “the first evidence for such behavior in a small inland lake,” according to a 2017 paper on their findings. 

By preserving Follensby as a scientific “reference site” on an 8,600-acre easement centered on the lake and allowing nature to run its course, the nonprofit and outside researchers hope careful study of the lake will yield insight into how to best protect cold-water fisheries in other lakes. 

While some anglers were left disappointed by the clear fishing prohibition going forward at Follensby, Bryant said as an avid fisherman he would sacrifice access to one out of 100 lakes if it helps improve fishing in 99 others.

Follensby is far from a pristine system —  non-native fish have established populations, including largemouth and smallmouth bass, yellow perch, sunfish and others. It’s not clear if fish were stocked in the lake in the past or the extent it has been fished historically. 

But the preserve will exist on thousands of acres of undeveloped watershed for researchers to study, including a wetlands network larger than the lake itself. TNC has already established woodland study sites.

Future research

Follensby’s deep, cold waters will provide increasingly rare refuge to cold-water fish as climate change continues to warm surface waters, while depleting oxygen in deep waters, the so-called “oxythermal squeeze” gradually choking off trout habitat in all but a few Adirondack lakes.

Its bathtub-shaped basin and 102-foot depth provides ample lake trout habitat. Study findings could signal for how other lake systems might respond to future changes.   

“Follensby is a fairly invaded system in terms of the fishery,” said Peter McIntyre, a Cornell water scientist. “But having a large volume of cold, oxygenated water is key for allowing cold-water species like lake trout to not be negatively impacted by invaders.”

McIntyre and other scientists said it will be important to begin collecting basic chemical and physical data on the lake as soon as possible, building out the foundational data that future research will rely on. TNC and DEC have started to collect information with a monitoring buoy, and the research consortium will plot how best to continue ongoing monitoring.  

While government and academic researchers often work together, McIntyre said those initiatives rely on extensive relationship building. At Follensby’s future research preserve, the lake will do a lot of that work.

“In this case we can rally around a place like Follensby and our shared interest in protecting it and using it as a sentinel for the broader system of Adirondack lakes,” McIntyre said. 

As a graduate student, Brendan Wiltse, a senior research scientist at the Adirondack Watershed Institute, spent two days on Follensby with a GPS and depth finder, collecting thousands of measurements. He helped update the lake’s bathymetric map.

“It’s a large, beautiful body of water that is really deep, which is not particularly common in the Adirondacks,” Wiltse said. “And to also be that remote, it’s definitely a very special place for a lot of reasons.”

AWI oversees long-term monitoring on dozens of lakes around the Adirondacks, including one of the most intensive in the region with a buoy on Upper Saranac Lake that collects data from the lake every four hours when the lake isn’t frozen. Wiltse said he hopes that Follensby can join those lakes with intensive monitoring and noted that AWI’s proximity can serve an important role for future research. 

Researchers also emphasized the value of working in a lake where access is limited, mitigating potential confounding variables that complicate studies on other lakes.

“Follensby fits nicely in this network of data we are collecting that can serve as a foundation for other researchers looking at fish populations and other aspects of ecosystems,” Wiltse said. “It’s beneficial to have this consistent long-term chemistry and physical data about water bodies, so we can provide necessary context for other research.”